Vacuum system for hydraulically operated mechanisms



May 7, 1935. H. F. VICKERS 2,000,265

7 VACUUM SYSTEM FOR HYDRAULICALLY OPERATED MECHANISMS Filed Mar ch so, 1931- INVENT v HARRY F. v/cm g BY MFM 6 A TTORNE) '8 Patented May 7,

PATENT OFFICE VACUUM SYSTEM FOR HYDRAULICALLY OPERATED MECHANISMS I Harry r. Vick'ers, Detroit, Mich. Appllcatlonltiarch so, 1931. Serial No. 526,192

comm.

able parts of hydraulically operated units.

, Heretofore in'the operation of hydraulic mechanisms such as presses and the like where a movable member such as a plunger is hydraulically moved through a stufilng box or the like, much 'difllculty has been experienced in the leakage and dripping of 011 after the machine or unit has been in'operation a comparatively short time. It is the object of the present invention to provide a simple means adapted to be connected to one or more hydraulic units for positively preventing any leakage or drippase between themovable member ormembers of such hydraulic unit or units.

More specifically, I have provided regulable vacuum creating means and suitable connections between such means and the stuiiing box or similar unit surrounding the movable unit of a hydraulic mechanism. The result is that this constantly maintained vacuum will serve to positively withdraw any oil which should leak past the packing so that the movable unit, such as a ram or the like, will always be clean and free from any leakage or dripping of oil.

In the drawing:

Fig. 1 is a somewhat diagrammatic view illustrating the manner of connecting up the vacuum creating means with a plurality of hydraulically operated imits, one of said units being shown partially in section to show the general assembly.

Fig. 2 is an enlarged detail view illustrating a manner of connecting the vacuum conduit to a standard stuffing box cylinder.

.' It will be understood that the present invention is adapted to be used with hydraulically 0perated mechanisms of practically every type. In order to best. illustrate the invention I have shown the sameas embodied in connection with hydraulic presses having what might be called a standard piston and cylinder construction.

In the left hand hydraulic unit of Fig. 1 I have shown a cylinder I having a piston 2 and a plunger or ram 3 forming a part of the press unit. The piston 2 is adapted to be operated hydraulically by means of operating fluid supplied through'the conduits 4 and 5. It will be understood, of course, that any suitable arrangement or connections may be used for operating the'piston as the present invention is not con- (c1. lav-rs) cemed with the type of fluid supply or the particular design of the member to be actuated.

The lower end of the cylinder I is shown as being provided with a standard stufling box unit 6 and to this stufling box unit is connected a 5 small tube or conduit I, preferably a small copper tube. This copper tube 'I may be connected to what might be termed a common line 8 and to this common line I is connected a vacuum conduit 9. A suitable pump III is connected to 10 the conduit 9 and this pump is preferably one of a simple inexpensive type as it is adapted to be used primarily only for creating a vacuum.

In order to obtain the most efllcient results the outlet of the pump III is connected by means 15 of a suitable conduit II to a supply tank I2 holding a supply of oil or other suitable liquid. The intake of the pump I0 is connected to this tank I! by means of a conduit l3 and somewhere between the intake of the conduit l3 and 20 the intake of the pump II is provided a suction relief valve ll adapted to regulably maintain a given vacuum. This suction relief valve may take various forms but roughly it is preferably provided with a suitable check valve l6 and a 25 regulable spring ii for controlling the opening. thereof and hence the amount of vacuum main 'tained by the pump Ill.

and hence out of the vacuum system.

The operation ofthe system is simple and 40 quite obvious. The pump l0, through the medium of the suction relief valve It, will serve tov continuously maintain any degree of vacuum that might be desired. This vacuum is, .of course, transmitted to the line 8 through the 45 conduit 9 andthe direct lead-ins I connect the stufling boxes with this vacuum whereby the respective stuffing boxes will be maintained under a certain degree of vacuum to thus positively remove any oil or other fluid that might 50 leak past the piston or operating member. While it is not important and does not form any particular part of the present invention, it will be understood that the tank l2 may be provided with anysuitable overflow in case of an over- 55 supply oi leakege and, desired, such over-flow 2. In a hydraulically operated mechanism 0! may be conducted to the regular fluid circulatingsystem.

sndssid devic e.'

What I claim is: 1; In e hydraulically operated mechanism of the type having n movable operating member, liquid supply means including a reservoir and a, pump and liquid under pressure for operating said-mechanism, e stumng 'box, and a conduit leading from the interior of said stumng box to a point between the reservoir and the pump;

menu for producing a positive suction in said stufling box comprising a restrictive device positioned between the reservoir and the point of connection of said conduit whereby the pressure inthempeiesdingintothepumpisdiminished relative to the pressure between the reservoir the type having a. movable operating'member and cylinder, liquid supply means including a. reservoir and a, pump and liquid under pressure for operstmg said mechanism, a stufllngbox tor normally preventing leakage from said cy1inder, and a conduit leading from the interior 012 said stumng box to a point between the reservoir and the pump, means for producing and maintaining a positive suction in said conduit and stufling b'ox comprising-a. regulable restrictive device. positioned between the reservoir and the point of connection or said conduit whereby the pressure in the pipe leading into the pump is diminished relative to the pressure between the reservoir snd said device.

. HARRY F. V'ICK'ERS. 

